Constant flow thermostatic control valve



March 2, 1954 c. D. BRANsoN CONSTANT FLOW THERMOSTATIC CONTROL VALVE Filed March 16, 1951 Patented Mar. 2, 1954 STANT THERMQSTTEC `CQNTROL Charles 1). Branson,

*valvebse'attmember 52 which islo'f sutableelas- :so im; .materia .tg 'gpovide yielaable engagement When the solenoid coil is energized to lift the armature 34, liquid in the tubular casing 30 may iiow freely therefrom through the axial passage 42 into the outlet passage I2. An unbalanced pressure is therefore set up on the valve member 38 due to the conical seating surface thereof being subjected to the pressure in the chamber 22 while the opposite end face thereof is subjected to the lower pressure in the outlet passage I2 by way of the axial passage 42. Consequently, a valve member 38 is lifted to permit fluid to flow freely from the chamber 22 into the outlet passage I2. When the solenoid is deenergized, however, the armature 34 is released to engage the conical end 35 with the valve seat 42 and thereby close the outlet from the tubular casing 30 through the axial passage 40. Fluid flowing through the clearance between the valve member 38 and the wall of the tubular casing 38 accumulates in the tubular casing 3G. Since this fluid is at substantially the same pressure as the fluid in the chamber 22, an unbalanced pressure is developed on the valve member 38 to cause the valve member 38 to move into engagement with its valve seat 26.

As each of the inlet passages 2U has a solenoidoperated valve functioning as described, energization of either solenoid for respectively actuating the associated valve member 38 to open position will result in either cold water or hot water from the nipples i6, I8 respectively being admitted to the common outlet passage I2. If both solenoids are energized and both valves 38 are open, then a mixture of hot and cold water is introduced into the common outlet passage l2.

As shown in Fig.`3, a -cup-shaped member 44 engages the wall of the inlet passage 28 and is provided in its bottom wall with a plurality of apertures 46. A flexible disc 48 formed of any suitable material such as rubber or neoprene is secured to the bottom wall over the apertures 46 by a pin or rivet 50. The disk 48 is of sufcient area to close the apertures 46 and constitute therewith a check valve to prevent reverse flow of the fluid through the inlet passage 26 when back pressure is present. However, the disk 48 is sufficiently flexible to move away from the apertures 46 and permit flow therethrough upon fluid pressure being applied to the disk 48 through the apertures 46.

As previously indicated, a constant iiow of fluid is maintained in the outlet passage I2 notwithstanding any variations of pressure of the fluid entering the inlet passages 20. To this end, the outlet passage I2 is provided with a plurality, in this instance three, tubular valve seats 52, 54, 56 which are spaced one from the other to provide a pair of annular ports 58, 60 aligned with the hollow valve seats 26, 28 respectively. It will be understood that the tubular valve seats 52, 54, 56 could be integral if desired and provided with suitable openings to form the ports B, 60 at the desired locations. It will also be understood that the portion of the outlet passage I2 which contains the tubular valve seats 52, 54, 56 constitutes a third valve chamber, l

A pair of sleevey valve members 62, 64 are mounted for reciprocation in the tubular members 52, 54, 56 so that the sleeve valve member 62 controls passage of fluid through the annular port 58 while the sleeve valve member 64 controls -flow of fluid through the annular port 60. A hollow valve stem 66 is secured by a spider or cross-arm connection 61 to the sleeve valve member 64 and extends longitudinally through the passage I2 toward the outlet conduit I4. The sleeve valve member 62 is also provided with a valve stem 68 in the form of a rod slidable within the hollow valve stem 66 and terminating therebeyond. The valve stem 68 may be secured to the sleeve valve member 62 by a spider or cross-arm connection 'I6 as in the case of the valve stem 66 and valve member 64. The sleeve valve members 62, 64 are thus adapted for independent operation, although means to be described are provided for joint operation at certain times.

The constant flow means takes the form of a pressure responsive device operable for moving both the sleeve valve members 62, 64 relative to the annular ports 58, 66 to maintain a constant rate of flow in the outlet passage l2. Accordingly, a `disk-like member 'I2 is formed integrally with the hollow valve stem 66 or may be suitably connected thereto. The disk 'I2 cooperates with the inner wall of an enlarged chamber 'I4 formed on the housing Il] at the end of the outlet pa..- sage I2 carrying the conduit I4. The periphery of the disk I2 has a predetermined clearance with the wall of the chamber 'I4 to provide an annular orifice of predetermined area therebetween. Biasing means in the form of a coil spring 16 is operative between the disk 'I2 and an end cap 18 for the chamber 'I4 which is secured to the casing i0 and forms a support for the conduit I4.

The thermostatic means for maintaining a constant temperature in the iiuid in the outlet passage is cperably associated with the pressure responsive means previously described. Thus, the valve stem 68 terminates in an end plate member 88 forming a bearing for one end of a coil spring 62 having its other end engaging the disk l2. An expansible member 84 forming a bellows element is secured at one end to the disk 12 and at the opposite end to the plate member 6l) for connecting the adjacent ends of the valve stems 66, 68 together. The thermostatic device is completed by the provision of a cup-shaped member 86 having its open end secured to the disk 'I2 and extending around the expansible member 84 to provide therewith a chamber 68. Thus, when the chamber 88 is lled with a iiuid such as ether or other fluid found to have suitable vapor pressure characteristics or expansion characteristics, then the expansible member 84 and the cupshaped member 86 form a cup-type thermostat well-known to the art.

From the foregoing, it is apparent that the coil spring 82 constitutes a thermostat load spring for urging the end plate 80, valve stem 68 and the expansible member 84 toward the bottom of the cup-shaped member 86 in opposition to the fluid charge in the thermostat. On the other hand, the coil spring 'I6 is a flow control load spring serving to react against the disk 'I2 to bias the entire assembly of disk l2, thermostatic device and sleeve valves 82, 64 to the left as viewed in Fig. 2. Since the wall of the chamber 'I4 is formed on a diameter larger than the diameter of the disk 12 a clearance is provided therebetween which remains the same size regardless of the position of the disk l2 under the vbiasing' movements described.

Operation When the solenoid valves are energized to open the valve members 38, then cold water flows into the annular port 58 through the sleeve valve 64 to mix with the hot Water which is flowing through the annular port 60. The mixed water flows on through the tubular member 56 around 5* the; disk, 'm and' the tnermostatic device te- `the outlet coind'uitA Il'. Wnentnein'ow ofrmixed fiuid around' the. diskn T2* reaches a certain retest-hen the: pressure drop;across tnevdisi:` 12 will" be surLA cient to' act on the' area' of' the` diei: 12'- annr create aforce inkexcess of the load on the spring T6. Under such conditi'oirs, the bia-s of the snring" 18. wili be suniciently overcome to' allow tn e disk 'Iz toi :nove to the-right,A as in Fig, 2.. Consequently; the sleeve valves 62, Se will benioved to a position which tends `tothrottle the now; through the annular; ports' 5"8; l? res'liectively and prevent the flow from increasing. This same balance betweenthe pressure drop ajcrosst tne d isliflzA` acting onthearea ofthe-disk 12j and the Ioad of the spring Teactsto'mai'ntain o constant rate of" flow regardiess: oifsuppisflprese temperature control' device does not affect trie finctioinng o'fA the constant' new device as previously descried However., due to the im c'iIsi'on of therrnostatic meansI operabiy associ-- ated With the`A constant flowL means", aconstant temperatur'ein th'eiiuid in the outlet passage can Bie maintained. Thus; ii the temperature of the mixed is' t'oo' high, their the lnd'fin the chamber es' wiliexpand to: contracty thc-member el andoverconre tnei bias oftnespring 82; therev byh increasing the distance between' the sleeve valves; 6'2; 6'4: This increase` in distance causes the disk lliL in ragniating.y the iiow to a constant rate' to move" the sleeve valves 62': es tok a position nearer the closed position relative to the annular ports' S8' and-6d. Hence, the ratio of" hotiwater to'r cold? Water making un the fixed total now willr be decreased. This increase intire properd tioiroi cold'w'a'terV and" decrease in proportion oi hot water tends'` to' bringthe; temperature of the n nxe'd' fluidi to tlra'",` temperature for' which the thermostat calibrated'- and produceequilibrium ofbotn temperatureand flow;

If the temperature ofthe mixture' is" too cold', then the fluid in the chamber 88`V wil-1fV contract eansi'ng an expansion ofthe member 8s" so that the bias of' the spring' 82 moves the valvestem es relativeto the valve stein Seite decrease the distance between the sleeve valves-62,- iig sona seqiently, thedisk 'iis caused tcrthrottle the coldt water andA increase the flow or not' waterwhich reverse action from that previously des criioedfl Coinsequentlv,l this; change in the proportion or hot and'l cold water tends to' increasethe temi llratuievof vthe' mixed fluidf ft' isi apparentn that" the thermostatic device andtlie* constant: fiow' device- Wili act in thel same manner toY deliver mixed fluid"Y at avk fixed rate of now and at constant temperature'- regardless of variations-mm1; and cold water supply temperatu-res` and pressures, or variationssinthe dit" ference hetween thehot and" cold water pressure. A simple, compact; valve'unithas been provided composed of parts which are easy to fabricate ancl assembie andi at the same time, the unit comprises a highly eicient constant flow thermostatie hot and cold water mixing valve;

Variousy changesr may 'he' made1 yin the details of construction and arrangement of parts within the scope of the appendedV claims,

Il claim;

i.t Valve mechanism comprising a housing having a plurality of inlet passages for ui'ds of different temperatnres having: an4 outlet passage for ifuid-intersected by a valve: chamben. a valve seat' in; said.. chamber and having port;- l.. L ans aiording communication between said passages,

acetico@ vo'A valvemeansi eoeeeraeie: said seat', for

ing and closing-said port means; means carriesY by? said: valve means andresponsive to uidteineperatures said" chamber for operating said valve means and maintaining a, constant aus@ temperature in' said' chamber" and constant lfictie mechanism in said*l chan'ilcerY opmativeiiy' con'a netted to the, assembly or saidvalve means saidthermally responsive means" for adjusting they same to'` posi-'tion said!v valve niearisY te rrfainew tain a constantrate offioweto said outlet passage; Valve mechanism comprising ah'ousing have ing a plurality oinie't passages forv iifuidsoi dife ferent temperatures and an'- ou-tlet passage for nui'crintersectedfty a valve chamber; a val-'ve seat said" chai-liber" and havingfport means aiirctif ing communication between sai-ciV passages;V vaife means 'cooper'aktfe' with said'- seatl *forV opening and ciosii'igsaid port means', pressurey respicnsive means lcarried by saidivalve meansand' coo'ner,Vey abie with awail of saidl cnamloer for'- donnine? an;orificey of" predetermined areameans fortiesiig said`p1s'su1e' responsive' maTI'Sj in' ai d-li'e# tion for' operatingsaid valverneans to* opeifr" port' means, saiti biasing' rrreansA being adapted tor be' over'c'onie by fuidpress'urein sain ciainier for maintainingja constant rate' cr now irs saisi outleifpassage, and thermos'tatie means carried by saidl valve means for= adjusting said` valve means' to" control the proportions of i'now through saillinletpa'ss'ae,'fesirespectivelyfois-rivalri-A taining a: constan-tv` temperat'iire'in theiiiirlf in saidoutle't passage` l 3: Valve-mechanism-connirisingia iioiisinenawen ing afiair of inlet passages forv hotantll cold' fluidrespect'ivelyandarrotlet'eassagefor'iniireri fiuid, said housinghavin'g a' chamber-*intersecting saidirrlet' and--outiet1pas'sages, a val-ve seatin` said chamber and' having" a pairorf ports affording cominimicationF betweensaid in-letf passages reSe spe'cti'vely and said'ontletpassage; apaireoff'va-lve members coopeif'aiijl'-ev Witlfl'- said* seatforV opening and' closing said ports respectiveiy, separate valve stems1- for' said valve-members for`- independent' operationthereof, thermostatci-meansfresponsive to* theL temperature of said; IniXed" finiti4 including afi expansible memberconnecting s 'Vailfv stems* and*operable for moving oi'ief-offsa yvalvfe" nlbl's relativ@ t0' the* other; vandf nlhSirSpoiw sive to fluid pressure inrsaid 'outlet passagefand operable formevingbotlrsairr vaivefmeinters1reif-1 ative to said ports to maintain a constant-*rat of now in' said outlet passage ata-constant temper aturedeterrnined bysaid thermostaticineansf 4i; Valve mechanism as" claimed int clairrr 3 wherein sai-'df `pressure'res'norisive mea-ns is coop*i erabi'e'j witherV waliof-saiki' clanflberV for'deining an orice of predeteriiiinedfarea, and: means* for Biasing saidi pressure" resp onsive incansfin-afdilieef tin for' Operating both Saidlike members ''O'l open said'ports, said biasingrneans being adapten foibe overcome"byT id pressure ier-maintain ng? saidv constantrate off ii'ow 'aid outletE passage; 5i" Valveineclanisnr coninrisinge*housinghave ing-a pairlorf inlet passages for: not colei respectivelyand: anoiitlet passage form fluid; said: housing havinga chamberv intersecting sainr inlet andi. outletV passages, a. tributari valve seat ini said chamber and. having, a-y pai-r'of annue` lar ports alording. communication between sai-di -n'let., passages respectively andT saldi outletflpassage,v a pair of, .sleeve valve members.k recinrocallei in saidseat for opening and closing saiijportsl respectively, separate. valve'stems slidaiile one within' theotfher and secured atene end thereof to said valve members respectively for independent operation thereof, thermostatic means responsive to the temperature of said mixed fluid including an expansible member connecting the opposite ends of said valve stems together and being operable for moving one of said valve members relative to the other, means operably associated with said thermostatic means for biasing said valve members toward each other in opposition to expansive movement of said expansible member, and means movable in response to pressure variations in said outlet passage and operatively connected to both said valve members for moving the same relative to said ports to maintain a constant rate or" now in said outlet passage at a constant temperature determined by said thermostatic means.

6. Valve mechanism as claimed in claim wherein said pressure responsive means includes a disk-like member carried by said other valve stem and being cooperable with a Wall of said chamber for dening an orice of predetermined area, and means operable between said disk-like member and an opposite wall of said chamber for biasing said other valve stem in a direction for operating both said valve members to open said ports, said last biasing means being adapted to be overcome by fluid pressure for maintaining said constant rate of flow in said outlet passage.

7. A valve mechanism unit including a single housing providing a valve chamber communicating with a single outlet passage, a pair ci inlet passages for respective connection to sources of hot and cold Water and a hollow valve seat connecting each of said inlet passages with said chamber, an independently actuated valve mechanism associated with each of said seats, said valve mechanism being operable between open and closed positions for controlling the water iiow between either or both of said inlet passages and said chamber, a valve seat in said chamber having port means affording communication between said passages, valve means cooperable with said last named seat for opening and closing said port means, constant flow valve mechanism operatively connected to said valve means for maintaining a constant rate of water iiow to said outlet passage upon operation of either or both of said first named valve mechanisms to said open position, and thermostatic means operably connected to said constant flow valve mechanism for adjusting said valve means to maintain a constant temperature in the water flow from said outlet passage.

8. A valve mechanism including a single housing providing a single outlet passage, a pair of inlet passages for respective connection to sources of hot and cold water and a hollow valve seat connecting each of said inlet passages with said outlet passage, an independently actuated valve mechanism associated with each of said seats, said valve mechanism being operable between open and closed positions for controlling the water iiow between either or both of said inlet passages and said outlet passage, a tubular valve seat in said outlet passage having a pair of ports aligned with said hollow valve seats respectively, a pair of valve members reciprocable in said tubular valve seat for opening and closing said ports respectively, pressure responsive means carried by said valve members and responsive to fluid pressure in said outlet passage for operating said valve members and maintaining a constant rate of flow through said outlet passage,.and

thermostatic means responsive to fluid temperatures in said outlet passage and operably connected to said pressure responsive means for adjusting said valve members to maintain a constant temperature in the fluid in said outlet passage.

9. A valve mechanism including a single housing providing a single outlet passage, a pair of inlet passages for respective connection to sources of hot and cold water and a hollow valve seat connecting each of said inlet passages with said outlet passage, an independently actuated valve mechanism associated with each of said seats, said valve mechanism being operable between open and closed positions for controlling the water flow between either or both of said inlet passages and said outlet passage, a tubular valve seat in said outlet passage having a pair oi ports aligned with said hollow valve seats respectively, a pair of sleeve valve members reciprocable in said tubular valve seat for opening and closing said ports respectively, separate valve stems for said valve members for independent operation thereof, thermostatic means responsive to fluid temperatures in said outlet passage including an expansible member connecting said valve stems and operable for moving one of said valve members relative to the other, and means responsive to fluid pressure in said outlet passage for moving both said valve members relative to said ports to maintain a constant rate of flow in said outlet passage at a constant temperature determined by said thermostatic means.

1G. Valve mechanism as claimed in claim 9 wherein said pressure responsive means is cooperable with a wall of said chamber for delining an orifice of predetermined area, and means for biasing said pressure responsive means in a direction for operating both said valve members to open said ports, said biasing means being adapted to be overcome by fluid pressure vfor maintaining said constant rate of flow in said outlet passage.

il. Valve mechanism comprising a housing having a plurality of inlet passages for uids of diiierent temperatures and an outlet passage for iiuid intersected by a valve chamber, a valve seat in said chamber having port means affording communication between said passages, valve n means cooperable with said seat for opening and closing said port means, constant now mechanism in said chamber for adjusting said valve means relative to said seat to control the total inow through said port means and thereby maintain a constant rate of flow to said outlet passage, and means responsive to uid temperatures within said chamber for adjusting said valve means relative to said seat to control the proportions of inflow to said inlet passages respectively and thereby maintain a constant fluid temperature in said outlet passage.

CHARLES D. BRANSYON.

References cites in the nie of uns patent UNITED STATES PATENTS Number Name Date 1,940,099 Hetherington Dec. 19, 1933 2,267,976 Hermann Dec, 30, 1941 2,321,573 Chace June 15, 1943 FOREIGN PATENTS Number Country Date 253,555 Switzerland Mar. 15, 1948 

